A constellation of satellites that gaze down on Earth will be the centrepiece of Britain's space mission if plans being put before ministers today are adopted.

The proposals from the government-appointed "Space Innovation and Growth Team" lay out a 20-year strategy that aims to expand Britain's space industry sixfold into a £40bn a year business and create 100,000 new jobs by 2030.

But one critic has claimed the proposals show "underwhelming" scientific ambition.

Under the plans, the space-based observatories could be used to monitor activity in war zones and gauge the progress of construction projects, crop harvesting and deforestation. They could also be used to police greenhouse gas emissions from foreign countries and even individual cities, according to the report by industry experts.

It urges the government to double its spending on space projects to £550m a year by 2020, a move that would lift Britain into the top 10 space-funding nations in the world. Today, the UK ranks 21st globally in terms of government support for space missions.

"The ball is just starting to roll on Earth observation and other space-based technologies and we need to be at the front of this to capture the market," said the head of the team, Terry Coxall, at the European space company Astrium. "We need government and companies to think about what they will want from space not now, but in five to 10 years' time."

He added: "Suppose the government wants to plan and monitor a high-speed rail link between London and Edinburgh. On Google Earth the images are updated about once a year. With an Earth observatory, you could have a fresh view from space every day and monitor progress from the computer on your desk. You don't need to trudge down to the site in your wellies."

The private space sector is a rare success story of British industry, growing at a steady 9% a year since 1999. It now contributes £6.5bn to UK GDP. Industry experts believe that with shrewd investment, Britain can grab 10% of a global market expected to be worth £400bn by 2030.

The report says industry needs to boost funding for research and development and raise more than £5bn for public finance initiatives to make headway in satellite technology in anticipation of a surge in demand for high-definition and 3D television broadcasts via space. Broadcasting programmes via satellites reduces costs and carbon emissions because it can be powered by the sun instead of using energy-hungry ground-based transmitters.

Solar-powered satellites will increasingly be used as orbiting internet hubs, too, a move that many scientists believe will be necessary to keep the carbon footprint of the internet under control as usage soars.

The report does not recommend that Britain pays into the European Space Agency's astronaut programme, despite Tim Peake, a former army helicopter pilot, being selected as the first Briton to join the agency's astronaut corps last year. Instead, the UK should use its backing of other space projects to argue for places on human exploration missions.

Professor Mark Sims at Leicester University's Space Research Centre said government and industry funding was now critical to take the proposals forward. "If the UK doesn't exploit the space market someone else will and we will be left behind. We are in a good position because of our historical investment in space, but we are at a tipping point. We cannot live on our past glories."

But Ian Crawford, a planetary scientist at Birkbeck College in London, said the report was underwhelming in terms of its scientific ambitions. In 2007, 14 of the world's space agencies signed a "global exploration strategy" that coordinates robotic and potential human missions to planets in the inner solar system. "The report doesn't carry that momentum on. This was the UK's chance to push for a leading role in the strategy to explore space."

Lord Drayson, the science minister, announced last year that Britain will open its own space agency in Harwell, Oxfordshire, to coordinate future space missions. The report calls on the government to fight for leadership of three upcoming European Space Agency missions as a means of gaining crucial experience in managing space projects.

"We need to play hardball to get the lead on missions rather than leaving it all to France and Germany," Coxall said. "If you are leading a mission you learn so much more and that puts you in a strong position for doing the commercial work that can spin off from it."